Manufacture of 6&#39;-chloro-6-methyl-1.2.3.4-tetrahydronaphthalene



Patented; Apr. 12, 1932' UNITED STATES PATENT? OFFICE;

GUSTAV REDDELIEN, OF ILEIPZIG, ANDiI-IAN S LANCE, OF'DESSAU IN ANHALT,GERMANY,

ASSIGNORS -T'0 WINTHRCP CHEMICAL CO CORPORATION OIE NEW YORK IMANUFACTURE OF 6-CHLORO-6-METHYL-1.2.3.4.-TETRAHYDRONAPHTHALENE NoDrawing. Application filed July 15, 1930, Serial No, 468,206, and inGermany July 29, 1929.

Our present invention relates to the manufacture of6-ohlor,o-6-methyl-12.3.4-tetrahydronaphthalene of the formula Hz 7 cueswin According-to our invention, 1.2.3.4-tetrahydronaphthalene istransformedrinto its 6- chloro-6-methyl derivative of the formula thereaction temperature may be varied with-e in certain limits and goodresults even are obtainable at temperatures between to 100 C. o 30 The6-chloro-6-methyl-1.2.3.et-tetrahydronaphthalene is a valuableintermediate product, for instance, in the manufacture of synthetic dyesor odoriferous substances.

The following example illustrates the invention without limiting it, theparts being by weight:

792 parts of 1.2.3.4-tetrahydronaphthalene are introduced into'a mixtureof 750 parts of an aqueous solution of formaldehyde of 30 .per centstrength and 3000 parts of concentrated hydrochloric acid. The mixtureis heated to C. to C. while stirring and introducing hydrogen chloride.After several hours the oil', is separated from the by drochloric acid,washed until" neutral, dried and distilledin a vacuum. Thus 702' partsof 6'-chloro 6 methylnaphthalene-tetrahyature of about 4:0 to 100 oilobtained may,of course, be directly used.

By a cautious oxidation process our new the reaction mixture. p

3. The process which comprises'acting with formaldehyde upon l.2.3.l-tetrahydronaphthalene in the presence of water and ofconcentratedhydrochloricacid at a temperature of about 60=to C. whilestirring the reaction mixture and while introducing gaseous hydrogenchloride. i

4. The process which comprises suspending 792 parts of1.2.3.4-tetrahydronaphthalene in 750 parts of an 3000 parts ofconcentrated hydrochloric acid, heating the mixture to 60 to 70 C. whilestirring and introducing hydrogen chloride;

5. As a new product 6 -chloro-6-methyl- 12.3.4-tetrahydronaphthalene ofthe formula under 11 mm. pressure of mercury and yielding bya cautiousoxidation process 1.2.3.4- tetrahydro-6-naphthaldehyde.

In testimony whereof, we afiix our signatures.

GUSTAV REDDELIEN. HANS LAN GE.

hide-1.2.3.4 are obtained, boiling between 139 C; and 141 C. under 11mm. pressure 59 of mercury. For technical purposes the crude PANY, INC.,OF NEW YORK, N. 'Y., .A.v

C. while stirring aqueous solution of formaldehyde of 30 per centstrength and

